<template>
  <el-container class="home_container">
    <!-- 头部区域 -->
    <el-header>
      <div>
        <img src="../assets/heima.png" alt="">
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button></el-header>
    <!-- 页面主体区域 -->
    <el-container>
      <!-- 侧边栏 -->
      <el-aside :width="isCollapse ? '64px' : '200px'">
        <div class="toggle_btn" @click="toggleCollapse">|||</div>
        <!-- 侧边栏菜单区 -->
        <el-menu
        background-color="#333744"
        text-color="#fff"
        active-text-color="#409eff"
        :unique-opened="true"
        :collapse="isCollapse"
        :collapse-transition="false"
        router
        :default-active="activePath">
        <!-- 一级菜单 -->
          <el-submenu v-for="item in menuList" :key="item.id" :index="item.id + ''">
            <!-- 一级菜单的模板区 -->
            <template slot="title">
              <!-- 图标 -->
              <i :class="iconsObj[item.id]"></i>
              <!-- 文本 -->
              <span>{{item.authName}}</span>
            </template>
            <!-- 二级菜单 menu中 开启 router index属性值当作跳转地址 -->
            <el-menu-item v-for="subItem in item.children" :key="subItem.id" :index="'/' + subItem.path" @click="saveNavState('/' + subItem.path)">
               <!-- 二级菜单的模板区 -->
              <template slot="title">
                <!-- 图标 -->
                <i class="el-icon-menu"></i>
                <!-- 文本 -->
                <span>{{subItem.authName}}</span>
              </template>
            </el-menu-item>
          </el-submenu>
         </el-menu>
      </el-aside>
      <!-- 右侧内容 -->
      <el-main>
        <!-- 路由占位符 -->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data () {
    return {
      // 左侧菜单数据
      menuList: [],
      // 图标集合 key是一级菜单的id
      iconsObj: {
        125: 'iconfont icon-users',
        103: 'iconfont icon-tijikongjian',
        101: 'iconfont icon-shangpin',
        102: 'iconfont icon-danju',
        145: 'iconfont icon-baobiao'
      },
      // 是否折叠
      isCollapse: false,
      // 被激活的链接地址
      activePath: ''
    }
  },
  created () {
    this.getMenuList()
    this.activePath = window.sessionStorage.getItem('activePath')
  },
  methods: {
    logout () {
      window.sessionStorage.clear()
      this.$router.push('/login')
    },
    // 获取左侧菜单数据
    async getMenuList () {
      const { data: res } = await this.$http.get('menus')
      // console.log(res)
      if (res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menuList = res.data
    },
    // 点击按钮菜单的展开与折叠
    toggleCollapse () {
      this.isCollapse = !this.isCollapse
    },
    // 保存链接的激活状态
    saveNavState (activePath) {
      window.sessionStorage.setItem('activePath', activePath)
      this.activePath = activePath
    }
  }
}
</script>

<style lang="less" scoped>
  .home_container {
    height: 100%;
  }
  .el-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding-left: 0;
      font-size: 20px;
      color: #fff;
      background-color: #373d41;
      > div {
        display: flex;
        align-items: center;
        span {
          margin-left: 15px;
        }
      }
  }
  .el-aside {
      background-color: #333744;
      .el-menu {
        border-right: none;
      }
  }
  .el-main {
      background-color: #eaedf1;
  }
  .iconfont {
    margin-right: 10px;
  }
  .toggle_btn {
    font-size: 10px;
    line-height: 24px;
    text-align: center;
    letter-spacing: 0.2em;
    color: #fff;
    background-color: #4a5064;
    cursor: pointer;
  }
</style>
